采用溶胶-凝胶技术制备溶胶,结合提拉法镀膜,通过溶剂替换工艺在常压下制备出了纳米多孔结构的V2O5气凝胶薄膜。使用TEM、BET、椭偏仪分别观测和测试溶胶的形貌、气凝胶孔径分布以及薄膜的折射率和孔洞率。采用标准三电极法研究了薄膜的电化学伏安循环特性以及恒流充放电性质。研究结果表明,常压干燥制备的薄膜孔隙率达到了56%,比干凝胶薄膜提高了16%,而且比容量达到530mAh/g左右,比干凝胶薄膜提高了33%,可逆性也得到了改善。研究表明,这些性能的提高归因于常压干燥气凝胶薄膜较高的孔隙率以及较大的孔洞直径。
Ambient dried V2O5 aerogel films are reported in this paper. The films are deposited by the dip coating method from V2O5 sols, followed the solvent exchange process. Ellipsometer, TEM, BET and electrochemical measurements are employed to characterize the aerogel films. The porosity of the aerogel films is 56 %, 16% higher than that of the xerogel films when dried at 120℃. The aerogel films have the higher capacity, 530mAh/g, as well as better reversibility than those of the xerogel filmS. The improvement of the capacity can be ascribed to the increase of porosity as well as the pore diameters after the solvent exchange.